Though posters are displayed in a public place as an announcement or advertisement, these days posters are limited to a piece of paper and particular place thus some pedestrians who pass by that street only can see.
This is art work from Jenny Holzer. In 1982, she presented her texts on the electronic notice board of Times Square.
The texts on the board emitting a series of unexpected phrases grabbed the attention of pedestrians whose average time of concentration is merely two to three seconds and aroused empathy among spectators in ways different from the art in the white cube. As her texts emitted a language which is a far cry from the stereotype, spectators reacted. It can be completed through the equivalence of her textual and spatial strategies.
The work making texts subject matter in open spaces using mapping for those unspecified is effective as poster because of its extensity of space and relative attention characteristic.
There is a limit in daytime. When utilizing shadow and dark wall or color light, we can enjoy all day.
http://projects.jennyholzer.com/projections/san-diego-2007/gallery#12